The objective of this project is to develop and test information visualization display technology that will aid clinicians in diagnosing and treating unexpected events in critical care environments. Unexpected events occur frequently in the ICU and many are related to missing, inaccurate or misinterpreted information. In a one year study of 1024 patients in an ICU, 241 human errors extended the stay in the ICU by 425 patient days and consumed 15% of the ICU's resources. Critical care clinicians discover critical events earlier and diagnose the events more accurately when data is presented in a graphic display. Preliminary studies found that when a graphic display of arterial blood gas information was used, the visual ABG display was more effective in communicating the status of the pH, PaCo2 and HCO3-values to the user, thus significantly increasing the situational awareness of the user. In addition, the display significantly increased the accuracy of the diagnosis while reducing cognitive workload. Our research plan is to build upon the successful results in phase 1 and extend the display to include more variables to give the clinicians a holistic understanding of the patients gas exchange state. Data-driven visual metaphors will be refined through an iterative design process. Usability testing will guide design enhancements. The resulting display will be implemented in C++ programming language. The utility of the graphic display will be measured using both a realistic patient simulator and a clinical ICU study. Thirty critical care clinicians will be called into a simulated ICU to assess the status of a patient in 4 different scenarios. Performance of the participants in the simulation will be evaluated based on the time to detect a given event, formulate a correct diagnosis, and provide effective supportive care. During the clinical evaluation we will place the new display in the ICU room and observe and record clinician's interventions and actions. Expert evaluators will rank order the performance of the clinicians both with the display and without. In addition, we will use a series of subjective instruments to ascertain information about desirability, perceived effectiveness and utility. This proposed display system has the ability to significantly increase patient safety by reducing the number of errors associated with misinterpretation of this information. In addition, it is anticipated that the new visualization system will have educational impact, as it will provide a clear demonstration and interaction of variables to both novices and experts alike. [unreadable] [unreadable] [unreadable]